"How can we denationalise national histories?" asks Shlomo Sand, quoting with approval the French historian Marcel Detienne, before sharpening the challenge in his own words: "How can we stop trudging along roads paved mainly with the forged materials of national fantasies?" This is the key issue in a book intended, from the title onwards, to be provocative.

Uncomfortable books, if they are good, can be important. National narratives do need deconstruction; they often blind us to different perceptions of the world and deafen us to the just claims of others. This is certainly true of the Middle East, and I am one of many Jews who would agree with Sand that a decisive factor in the future of Israel will be its capacity to be far more attentive to the narratives and rights of its Palestinian and other non-Jewish citizens.

But the book is a great disappointment. Its sweeping attempt to take apart the entire history of the Jewish people from its origins to present day Israel and prove it to be a wilful fabrication is marred by tendentious premises, the misreading of key events and the ignoring of central texts and institutions.

Sand's argument begins with 19th century European concepts of nation- and people-hood. He maintains that Jewish historians such as Graetz were deeply influenced by Germanic notions of the "Volk" on which the idea of the modern state is built. This nationalism was sharpened by the discourse of race and eugenics current then and later in Europe, with such disastrous results for Jewry. Sand traces a line from Graetz to the Zionist historians who, he argues, employ such bioethnic concepts to invent an imaginary entity, a racially continuous Jewish people who were exiled from their land, and therefore deserve to return to it 2,000 years later. Such continuity, argues Sand, is a fiction and the Jewish people are therefore an "invention".

A key point for Sand is the fate of the Jews after the destruction of the temple in Jerusalem by the Romans in 70CE. Sand attempts to prove that the exile of the Jews in the wake of this and subsequent defeats never happened. It is a fiction of modern Jewish historiography: hence neither later North African nor European Jewish communities can be the products of a diaspora of exiles, but are rather the result of mass conversions of the most racially diverse populations. Therefore there is no genetic continuity between today's Jews and those who once inhabited ancient Judaea.

The flaws in Sand's argument are both historical and conceptual. The idea of exile, he suggests, was adopted from the Christian view that the Jews were punished with dispersion for the crime of killing Jesus. But this makes no sense. The paradigm of exile and return is found in the Bible in Deuteronomy and Jeremiah in relation to the destruction of the first temple by the Babylonians in 576BCE. It is thus part of the Jewish narrative centuries before Christianity. Further, contrary to what Sand maintains, serious historians of the period consider that the Romans did indeed kill or sell as slaves very many thousands of Jews. The rest of the population was banned from access to Jerusalem, which was renamed Aelia Capitolina. This would surely engender a sense of exile in any people.

What is indisputable is that early Jewish communities grew through conversion. But Sand's key thesis, that the bulk of modern eastern European Jewry owes its origins to the converted kingdom of the Khazars, has been widely debated, and rejected, especially in the wake of Arthur Koestler's famous book on the subject. Sand's allegation that this whole episode was hushed up because it vitiated the Zionist notion of Jewish ethnobiological continuity, cannot be maintained.

Equally important is what Sand fails to discuss. To vast numbers of Jews, arguments about racial origins are both ugly and, more importantly, irrelevant. Instead, Jewish continuity is premised on religious factors, including observance of the Torah, the study of the Talmud, the creation of communities, the life of the synagogue and the bonds of the liturgy. These are what form the vital links between generations of Jews. To examine Jewish history almost without reference to its religious life and literature is like attempting to discuss Islam without mentioning the Hadith, the Shariya or the role of the Muslim community. Whereas Sand is quite right that Jewish life has always reflected local cultures, his claim "that there had never been a Jewish people's culture" cannot be taken seriously.

Sand virtually ignores persecution and antisemitism as contributory factors in forming Jewish narratives, just as he omits the role of hostility towards it in fashioning Israeli attitudes later.

In the final chapter Sand offers a severe critique of the limitations of Israeli democracy. It is a tribute to the country's liberalism, which he acknowledges despite deep reservations, that his book has been widely read there. Rejecting the practicability of a bi-national state, he stresses the urgent need for an end to the occupation and for the genuine equal participation of all the country's citizens in its civic processes if it is to avoid profound conflicts within its pre-67 borders. In this, I agree.

Sand makes it clear from the outset that he identifies with those excluded by the Jewish-Israeli narrative. Regrettably, the book lacks the empathy for the outsider which one might have expected. Instead, it is driven by a sustained polemic against a misreading of Judaism imposed more by the author himself than by those "authorised historians" whose supposed repression of "cheeky little facts" he sets out to unveil. Ironically for a book intended to deconstruct myths, it may well be taken up by those with an alternative mythology in which the Jews have no right to a state at all. Sadly, this would be unlikely to further the interests of Palestinians, or Israelis, or peace.

Jonathan Wittenberg is rabbi of the New North London Synagogue. His books include The Silence of Dark Water: An Inner Journey (Robin Clark/Joseph's Bookstore).